A standard heat-insulating connecting member normally comprises a warm metal profile, a cool metal profile extending parallel to and spaced from the warm profile, and a pair of parallel and spaced insulating strips bridging the profiles and defining an insulating compartment therebetween. Normally one of the strips is formed with a web provided with an layer that blocks or reflects infrared (IR) radiation. The so-called warm profile is the part of the member in cold climates and the outside part in hot climates and the IR-blocking or -reflecting layer serves to prevent radiant energy from passing through the connecting member from its hot side to its cold side.
In German utility model 94 11 396 the IR blocker is a metal-oxide layer that is simply painted onto the transverse web and is typically reflective. While this system works very well when new, with time it gets dirty and loses its ability to reflect, thereby reducing the R rating of the connecting member. Furthermore if the connecting member is anodized or hot lacquered, as is common when the profiles are aluminum, the IR-reflective layer is frequently destroyed. As a result such IR-blocking connecting members have not gotten past the theoretical stage into actual use.
European patent application 0,807,833 of Yamashita (Japanese priority of May 17, 1996) describes a reflective foil used in a projection television. Such a foil is extremely effective but is subject to the same degradation or destruction if mounted in a profile member that is subsequently heat-treated or anodized.